This invention relates generally to vacuum cleaners and, more particularly, to vacuum cleaners capable of picking up both liquid and dry material from a surface being cleaned.
In large wet/dry vacuum cleaners, it is easier to design a unit which will provide good liquid separation and storage and also will provide relatively large filter area for maintaining cleaner efficiency when picking up dry material. However, in small units where space is at a premium, the design of unit to provide good liquid separation and storage, and also good filtration capability for dry mode operation becomes much more difficult. As a result, many such compact wet/dry units often sacrifice performance capability in either the wet or dry mode by, for example, reducing dry material filtering capability by use of small filters. A filter with a small filter area will clog or have the filter area substantially reduced within a short period of time thereby reducing air flow through the unit which substantially impedes its ability to pick up both liquid and dry material at its intake nozzle.
Further, compact units such as hand held wet/dry vacuum cleaners are often utilized to pick up liquids other than water such as, for example, milk and cereal spills. Thus, it is highly desirable to provide a compact wet/dry vacuum cleaner which can be easily cleaned after use.
Still further, it is important in any wet/dry unit to provide good seals to prevent liquid spillage from its storage container and also to provide good cleaner performance by assuring that air flow and suction pressure generated by the motor and fan of the cleaner is available at the cleaner's nozzle for pick up of the material. This is particularly important in compact wet/dry vacuum cleaners since often a relatively small power source must be used because of space limitations. Thus, poor seals can substantially reduce performance of the vacuum cleaner and cause spillage of liquid which could damage carpet or other materials.